Need help with long 1000' wire run

[ard]

Basically 4 transformers, beginning and end of each of the 2 runs. Up to 480v, down to 240v, subpanel, rest of circuit?

Two; one up...one down. ebay will be your friend.

The rating will be in kva. if, say, you want 20A, then 20X120=2400=2.5kva.

And therein lies the key. at 480V in the long run, you only need **5 Amps** (5x480=2400) to supply that 20A@120. And the voltage drop due to pushing 5 A in #8 is far less.

 

[ard]

So how is what I recommended any different than the transformer on the pole in my back yard ?

High voltage input on one side. Split phase 240VAC on the other.

You dont use a transformer to *boost* voltage drop when the load is variable. As the load changes the voltage will overboost/underboost .

 

[Sama8525]

Two; one up...one down. ebay will be your friend.

The rating will be in kva. if, say, you want 20A, then 20X120=2400=2.5kva.

And therein lies the key. at 480V in the long run, you only need **5 Amps** (5x480=2400) to supply that 20A@120. And the voltage drop due to pushing 5 A in #8 is far less.

So what happens if i plug it into 20amp instead of 5? How much do i end up with?


So effectively i need one like this? https://www.amazon.com/dp/B007IBV1R0/?tag=atomicindus08-20

 

[ard]

Please Please Please. Get someone to help you.

The questions you are asking mean you arent comprehending to a level that makes it safe to buy stuff

IMO.

The description gave means yu **CAN** plug in 20A at the far end. It will draw 20 amps at the far end. HOWEVER, along the long wire run, WHERE THE VOLTAGE IS 480, it will only be running 5 Amps.

Taking a quick look, that seems like a step down transformer for the far end. But get someone to design it for you.

 

[theoldwizard1]

The description gave means you **CAN** plug in 20A at the far end. It will draw 20 amps at the far end. HOWEVER, along the long wire run, WHERE THE VOLTAGE IS 480, it will only be running 5 Amps.

Some wire insulation is rated for 600V. Some is only rated for 300 !

 

[theoldwizard1]

And therein lies the key. at 480V in the long run, you only need **5 Amps** (5x480=2400) to supply that 20A@120. And the voltage drop due to pushing 5 A in #8 is far less.

Why bother boosting to 480V when 240V direct off of the main panel is available (through a breaker of course) ? You would still only be talking about 10A.

Need to price only one custom wound transformer. Have the primary wound for multiple input voltages (200/210/220/230/240) and the output wound for 240 split phase which could be used as one 240V, two 10A 120VAC legs or one 20A 120VAC leg.

 

[theoldwizard1]

Please Please Please. Get someone to help you.
.
.
.
But get someone to design it for you.

A certified electrical engineer !

 

[Baydog]

There are a number of online calculators for determining the right wire size. You need to know the total amp draw, the voltage whatever your operating is running at. Then you can play with cooper vs aluminum and wire size. here's an easy to use one:
https://www.calculator.net/voltage-drop-calculator.html

 

[Sama8525]

Please Please Please. Get someone to help you.

The questions you are asking mean you arent comprehending to a level that makes it safe to buy stuff

IMO.

The description gave means yu **CAN** plug in 20A at the far end. It will draw 20 amps at the far end. HOWEVER, along the long wire run, WHERE THE VOLTAGE IS 480, it will only be running 5 Amps.

Taking a quick look, that seems like a step down transformer for the far end. But get someone to design it for you.

I definitely will with the transformers, thats past my level of knowledge. But i also want to get a good idea of what to have them do before they come out and quote me the most expensive option

 

[ard]

Why bother boosting to 480V when 240V direct off of the main panel is available (through a breaker of course) ? You would still only be talking about 10A.

Need to price only one custom wound transformer. Have the primary wound for multiple input voltages (200/210/220/230/240) and the output wound for 240 split phase which could be used as one 240V, two 10A 120VAC legs or one 20A 120VAC leg.

Because his #8 at 10Amps will ONLY get him to 521 feet ( I ran a quick VD calc on southwires VD calculator)

480 gets him to 1042'

no 'custom transformer' needed. Insisting on a custom transformer and a 'certified electrical engineer' is making this (sound) way more complicated than it is. Are you trying to help the OP or make some kind of a point?

 

[ard]

I definitely will with the transformers, thats past my level of knowledge. But i also want to get a good idea of what to have them do before they come out and quote me the most expensive option

You will likely find a good number of 'electricians' dont know how to do this. Dont assume the guy you have 'come out' will be qualified.

 

[teamextreme]

Just a thought; I don't recall any NEC restrictions, but this would be a pretty obscure rule I may not remember, but seems I've heard it mentioned before: is it even code legal to have 480V on a residential property?

In terms of this overall issue, I think you're making this way too complicated for a need that in reality is unnecessary. Your actual load, if you get rid of the idea of powering tools and compressors at this distance, is very low amperage (likely under 2A?), which is doable with your #8. Run it to power your lights/cameras and be done.

 

[theoldwizard1]

Because his #8 at 10Amps will ONLY get him to 521 feet ( I ran a quick VD calc on southwires VD calculator)

480 gets him to 1042' (without significant VD)

Okay, but I think one custom transformer with multiple input taps will be cheaper !

Insisting on a custom transformer and a 'certified electrical engineer' is making this (sound) way more complicated than it is. Are you trying to help the OP or make some kind of a point?

No point to make. Ijust think it would be cheaper and easier. Clearly, this discussion is way over the OPs "grade level". Maybe a really good sparky could handle the job.

If I went with your proposed solution, I would want a fuse/breaker on the output of the "upstream" transformer, "just in case" !

 

[theoldwizard1]

In terms of this overall issue, I think you're making this way too complicated for a need that in reality is unnecessary. Your actual load, if you get rid of the idea of powering tools and compressors at this distance, is very low amperage (likely under 2A?), which is doable with your #8. Run it to power your lights/cameras and be done.

But that is what we do here on GJ ! (Kind of like German cars theses days.)

You are probably correct and those are the only loads, they will probably work down to about 100VAC !

 

[brewchief]

In terms of this overall issue, I think you're making this way too complicated for a need that in reality is unnecessary. Your actual load, if you get rid of the idea of powering tools and compressors at this distance, is very low amperage (likely under 2A?), which is doable with your #8. Run it to power your lights/cameras and be done.

I agree, use leds for lighting to keep the amperage low, if you need to use a saw or drill I bet you wouldn't even know if the voltage drop was a few volts more then ideal. I've been on job sites that have multiple saws running at one time off of several hundred feet of extension cord, voltage drop there is going to be worse.

If you can run 4 wires to a small subpanel that would be better but don't overcomplicate it.

Sent from my SM-G965U using Tapatalk

 

[dave*99]

Why bother boosting to 480V when 240V direct off of the main panel is available (through a breaker of course) ? You would still only be talking about 10A.

Need to price only one custom wound transformer. Have the primary wound for multiple input voltages (200/210/220/230/240) and the output wound for 240 split phase which could be used as one 240V, two 10A 120VAC legs or one 20A 120VAC leg.

This is bad advice. See post 42 for an explanation. A multi tap transformer is not a solution when the load is variable.

 

[wyliesdiesels]

Why bother boosting to 480V when 240V direct off of the main panel is available (through a breaker of course) ? You would still only be talking about 10A.

Need to price only one custom wound transformer. Have the primary wound for multiple input voltages (200/210/220/230/240) and the output wound for 240 split phase which could be used as one 240V, two 10A 120VAC legs or one 20A 120VAC leg.

Okay, but I think one custom transformer with multiple input taps will be cheaper !



No point to make. Ijust think it would be cheaper and easier. Clearly, this discussion is way over the OPs "grade level". Maybe a really good sparky could handle the job.

If I went with your proposed solution, I would want a fuse/breaker on the output of the "upstream" transformer, "just in case" !

no no no

one transformer design doesnt work unless its an auto transformer with auto adjusting taps like a PoCo uses on a substation.

The load is variable. you cant use a fixed tap transformer for a variable load. The voltage would fluctuate.

Your design is poor.

 

[TractorJeff]

Could put a Buck/Boost on to up the "transmission" voltage to get it out there at an acceptable value. Like mentioned before a 120 volt motor running at 130 or 110 will never notice the difference. I think the old house transformer had my panel at 245? I haven't checked the new pole mount yet. Should though because they promised an upped transmission line with pad mounts to negate Ice issues.

 

[dave*99]

Could put a Buck/Boost on to up the "transmission" voltage to get it out there at an acceptable value. Like mentioned before a 120 volt motor running at 130 or 110 will never notice the difference. I think the old house transformer had my panel at 245? I haven't checked the new pole mount yet. Should though because they promised an upped transmission line with pad mounts to negate Ice issues.

Bad advice. A buck boost transformer is not useful when the load is variable. Same issues as Old Wizards call for a custom wound multi-tap transformer. Read the posts that address that for an explanation.